How to make Laezel stay with you after you become mind flayer?

[Tjoa Jun Choi]

I see someone in YouTube uploading a video where Lae'zel choose to stay with mind flayer Tav. I want to get this ending but Lae'zel keep rejecting me and go with Orpheus instead. Is anybody now how to get this specific ending?

[Orion Invictus]

You can't. You're a Mind Flayer now, the thing she hates the most.

[Tjoa Jun Choi]

See this video: https://www.youtube.com/watch?v=HIz1_Ub1xAI

I also believe at first that Lae'zel will always leave us. But this video proof that Lae'zel actually can stay after we become mind flayer. The problem is, I don't know how to trigger the scene